1. Field of the Invention
The present invention relates to personal telephone systems that are able to transmit and receive digital signals between fixed sets and fixed stations in a cordless system. More particularly, the present invention relates to providing the capability of providing a broadcast over broadcast mode in a cordless telephone system.
2. Description of the Related Art
Time division multiple access (TDMA) cordless phone systems provide a base unit which is able to provide connections for a plurality of mobile units, such as handsets. Such TDMA systems use time division to provide a plurality of slots, where the base (fixed part (FP)) transmits to an individual (portable unit (PP)) mobile unit during a particular slot of time and receives from the individual mobile unit during a particular slot of time. One standard for TDMA systems is the Digital European Cordless Telecommunications DECT Common interface standard described in ETS 300 175-2 and ETS 300 175-3, published by the European Telecommunication Standards Institute. The DECT standard is also discussed in U.S. Pat. No. 6,078,574 entitled xe2x80x9cPROCESS AND APPARATUS FOR ACTION CONTROL IN A TIME SLOT METHODxe2x80x9d, to Boetzel et al. issued Jun. 20, 2000 and U.S. Pat. No. 6,088,338 entitled xe2x80x9cMETHOD AND SYSTEM FOR THE DETERMINATION OF THE PSCN PARAMETER STARTING FROM THE MFN PARAMETER IN A DECT CORDLESS TELEPHONE SYSTEMxe2x80x9d to Rossella et al. issued Jul. 11, 2000, which are incorporated by reference. Generally, the DECT standard does not provide a specification to send a voice message to all mobile units simultaneously as a broadcast.
Due to this limitation, it is not possible to broadcast a streaming audio signal, such as RealAudio(trademark), over a conventional cordless phone system thereby providing the capability of listening to broadcast news, for example, while still maintaining the ability to use the cordless phone to send and receive phone calls.
Therefore, in a cordless phone system having a base station and a mobile unit, it is desirable to provide a broadcast over broadcast mode that enables a user to both listen to a streaming audio signal yet still maintain the ability to both send and receive conventional telephone calls.
To achieve the foregoing and other objects and in accordance with the purpose of the present invention a call screen over broadcast mode in a cordless telephone system is provided. Generally, a cordless telephone base unit in a broadcast mode receives a radio or streaming audio signal. A call controller unit included in or coupled to the base station then sends the received radio or streaming audio signal to at least one mobile unit in communication with the base station. In those cases where a mobile unit is receiving the broadcast and a conventional phone call is received at the base station, then a determination is made whether or not to send the conventional call to the mobile unit is made. In those cases where the conventional call is to be forwarded, then the base station is set to standard mode and the conventional call is forwarded to the mobile unit whereas any other mobile unit in communication with the base station still receive the broadcast.
When the conventional phone call has been completed, the base station is set to broadcast mode where the mobile unit commences to again receive the broadcast.
In another embodiment, a cordless telephone system is disclosed. The cordless telephone system includes a base station operable in a broadcast mode and a standard mode and a mobile unit in communication with the base station. In a preferred embodiment, when the base station is broadcasting a signal to the mobile unit in the broadcast mode and when it is determined that an incoming message is to be forwarded to the mobile unit, the base station is set to the standard mode until incoming message is terminated.
These and other features of the present invention will be described in more detail below in the detailed description of the invention and in conjunction with the following figures.